This invention relates broadly to generators, and has particular reference to a novel generator and method for producing electricity from piezo electric material by means of a vaporized refrigerant that acts on the piezo electric material, the pressure of the refrigerant being varied to cause it to exert mechanical forces on the piezo electric material.
Apparatus has been developed heretofore for generating electricity by means of a gas under pressure. Thus, U.S. Pat. No. 3,080,515 to E. C. Kehoe discloses methods and apparatus for developing electrical energy by means of a gas driven arc. U.S. Pat. No. 3,405,334 to H. H. Jewett et al discloses an electrostatic generator wherein the plates of a variable capacitor are enclosed in a vacuum chamber and their separation is varied by pneumatic means to produce a current. U.S. Pat. No. 4,288,735 to R. C. Crites discloses a vibrating electret reed voltage generator wherein the reed vibration is induced by fluid pressure supplied to the reed chamber and controlled through a fluid oscillating circuit. None of these patents discloses a generator that utilizes piezo electric material in combination with a vaporized refrigerant under varying pressure as in the present invention.
Other but less pertinent patents noted in the course of a preliminary search are U.S. Pat. Nos. 3,593,110 and 4,220,906 and Russian Pat. No. 656,167 (1979).
The closest prior art known to the applicants is U.S. Pat. No. 3,665,226 granted May 23, 1972 to R. A. Sinker et al. The Sinker patent is directed to an electric generator operated by means of the flow of a fluid against a diaphragm to which a piezo electric material is secured. The fluid flows into a cavity and exhausts from the cavity between the diaphragm and a closely spaced annular shoulder. Pressure variations within the cavity caused by flexure of the diaphragm create a self-sustained diaphragm vibration for generation of electricity by the piezo electric material.